It has long been recognized that the job turnover of women exceeds that of men. This difference in turnover is blamed for the persistent sex-related wage differential. Economic research has up to now focused only on the labor-force turnover of women. The proposed study will extend the framework to analyze also inter-firm mobility. Given the close relationship between that form of mobility and the investment in specific human capital, I shall examine its optimum path over the life cycle, the optimum mix of general and specific investment, and the effect of labor turnovers on this mix. The factors determining women's inter-firm mobility and its effect on wage growth will be analyzed.